CN114578677B

CN114578677B - Suspension type chip atomic clock physical system

Info

Publication number: CN114578677B
Application number: CN202210164101.7A
Authority: CN
Inventors: 孟红玲; 苏其明
Original assignee: Zhongke Qidi Optoelectronic Technology Guangzhou Co ltd
Current assignee: Zhongke Qidi Optoelectronic Technology Guangzhou Co ltd
Priority date: 2022-02-22
Filing date: 2022-02-22
Publication date: 2023-05-26
Anticipated expiration: 2042-02-22
Also published as: CN114578677A

Abstract

The application discloses suspension type chip atomic clock physical system, the support frame is installed in the LCC base, U type frame, the air chamber support, second heating plate and detector set gradually on the support frame from bottom to top, laser instrument base has been set gradually in the direction that is close to the second heating plate in the U type frame, the backing plate, the decay piece, 1/4 wave plate and first heating plate, VCSEL laser instrument and thermistor are installed on the laser instrument base, the atomic air chamber is installed in the air chamber support, the getter sets up peripherally at U type frame and air chamber support, ceramic pipe cap is installed peripherally and LCC base seal welding at the getter. The suspension type chip atomic clock provided by the invention has the advantages of high physical system strength, lower power consumption, simple structure and low production cost, and provides a solid foundation for public application of the chip atomic clock.

Description

Suspension type chip atomic clock physical system

Technical Field

The application relates to the technical field of atomic clocks, in particular to a suspension type chip atomic clock physical system.

Background

Atomic clocks are a high-level standard and tool for measuring time and frequency. The atomic clock utilizes a very stable energy level structure in the atoms, and the atomic clock is slightly influenced by external conditions, so that the atomic clock has very high accuracy and stability, and can be used in various fields such as high-precision time service, precise measurement, satellite navigation positioning, high-speed communication and the like.

The traditional atomic clock has larger volume and power consumption and high corresponding cost, which limits the application of the atomic clock to a great extent. For example, in the case where satellite signals are not acceptable for submarine navigation, underwater operation, and the like, and in high precision manufacturing, the demand for a miniaturized atomic clock with low power consumption is particularly urgent and necessary. The chip atomic clock based on the atomic Coherent Population Trapping (CPT) phenomenon has the advantages of low power consumption, small volume, portability, available battery power supply and the like over the traditional atomic clock.

The physical system is the core of the chip atomic clock, and the performance of the physical system directly determines the performance and index of the atomic clock, and also determines the whole volume and power consumption of the atomic clock to a great extent. The chip atomic clock physical system existing in the current market has the defects of complex structure, high manufacturing cost, lower strength, higher power consumption and the like, and limits the application of the chip atomic clock.

Disclosure of Invention

Therefore, the application provides a suspension type chip atomic clock physical system to solve the problems of complex structure, high manufacturing cost, lower strength, higher power consumption and the like in the prior art.

In order to achieve the above object, the present application provides the following technical solutions:

the utility model provides a suspension type chip atomic clock physical system, includes LCC base, support frame, laser instrument base, VCSEL laser instrument, thermistor, spacer, U type frame, attenuator, 1/4 wave plate, first heating plate, air chamber support, atomic air chamber, second heating plate, detector, getter and ceramic pipe cap, the support frame is installed in the LCC base, U type frame air chamber support, second heating plate with the detector sets gradually from bottom to top on the support frame, be close to in the U type frame the direction of second heating plate is provided with in proper order the laser instrument base, spacer the attenuator 1/4 wave plate with first heating plate, VCSEL laser instrument with thermistor installs on the laser instrument base, the detector just to the transmitting end of VCSEL laser instrument, the atom air chamber is installed in the air chamber support, the getter sets up U type frame with the air chamber support periphery, ceramic pipe cap installs the welding of VCSEL laser instrument with the getter is sealed.

Preferably, the support frame comprises a silicon frame and a polyimide film, wherein the polyimide film is hollowed out and arranged in the middle of the silicon frame, and the U-shaped frame, the air chamber support, the second heating plate and the detector are sequentially arranged on the polyimide film from bottom to top.

Preferably, the polyimide film is a photosensitive polyimide.

Preferably, the polyimide film has a thickness of 10 μm.

Preferably, the silicon frame is made of hexagonal crystal silicon.

Preferably, the laser base, the first heating plate and the second heating plate are made of glass or quartz.

Preferably, metal electrodes are vapor-deposited on the laser base, the first heating sheet, and the second heating sheet.

Preferably, the U-shaped frame and the air chamber support are made of silicon.

Preferably, the getter is made of a multi-metal material.

Preferably, the atomic gas chamber is a square or spherical gas chamber.

Compared with the prior art, the application has the following beneficial effects:

1. all components are in the same cavity for integral temperature control, instead of respectively controlling the temperature of the VCSEL laser and the atomic gas chamber, so that the whole structure of the system is simpler, the production cost is lower, the vacuum reflow soldering can be realized, the power consumption of the equipment is reduced, and a solid foundation is provided for the public application of chip atomic clocks;

2. the support separates the laser base and the components such as the 1/4 wave plate, the attenuation sheet, the heating sheet, the atomic air chamber and the detector on the laser base from the LCC base, so that heat conduction and loss are reduced, meanwhile, the PI film of the support is hollowed out in the shape of a Chinese character 'jing', the contact area between the PI film of the support and the laser base is reduced, heat conduction and loss are reduced, and the effect of reducing equipment power consumption can be achieved.

3. Various materials such as glass, quartz, metal, silicon, high polymer materials, ceramics and the like are adopted as basic materials, so that the selection range is wide, and all the connections are bonded by adopting high-strength adhesives, so that the strength is high;

4. realizing vacuum reflow soldering and reducing the power consumption of equipment;

5. provides a solid foundation for public application of chip atomic clocks.

Drawings

For a more visual illustration of the prior art and the present application, several exemplary drawings are presented below. It should be understood that the specific shape and configuration shown in the drawings should not be considered in general as limiting upon the practice of the present application; for example, based on the technical concepts and exemplary drawings disclosed herein, those skilled in the art have the ability to easily make conventional adjustments or further optimizations for the add/subtract/assign division, specific shapes, positional relationships, connection modes, dimensional scaling relationships, etc. of certain units (components).

Fig. 1 is a schematic diagram of the overall structure of a physical system of a suspension chip atomic clock according to an embodiment of the present application;

fig. 2 is an exploded view of a physical system of a suspension chip atomic clock according to an embodiment of the present application;

fig. 3 is a schematic structural diagram of a support frame according to an embodiment of the present application.

Reference numerals illustrate:

1. an LCC base; 2. a support frame; 21. a silicon frame; 22. a polyimide film; 3. a laser base; 4. a heightening sheet; 5. a U-shaped frame; 6. an attenuation sheet; 7. a 1/4 wave plate; 8. a first heating plate; 9. an air chamber bracket; 10. an atomic gas chamber; 11. a second heating plate; 12. a detector; 13. a getter; 14. a ceramic pipe cap; 15-VCSEL lasers; 16-thermistor.

Detailed Description

The present application is further described in detail below with reference to the attached drawings.

In the description of the present application: unless otherwise indicated, the meaning of "a plurality" is two or more. The terms "first," "second," "third," and the like in this application are intended to distinguish between the referenced objects without a special meaning in terms of technical connotation (e.g., should not be construed as emphasis on degree or order of importance, etc.). The expressions "comprising", "including", "having", etc. also mean "not limited to" (certain units, components, materials, steps, etc.).

The terms such as "upper", "lower", "left", "right", "middle", and the like, as referred to in this application, are generally used for convenience in visual understanding with reference to the drawings, and are not intended to be an absolute limitation of the positional relationship in actual products. Such changes in relative positional relationship are considered to be within the scope of the present description without departing from the technical concepts disclosed herein.

Referring to fig. 1 and 2, an embodiment of the present invention provides a suspension chip atomic clock physical system, which includes an LCC base 1, a support frame 2 (also referred to as "silicon frame-PI film"), a laser base 3, two glass elevating sheets 4, two U-shaped frames 5, an attenuation sheet 6, a 1/4 wave plate 7, a first heating sheet 8, a gas cell support 9, an atomic gas cell 10, a second heating sheet 11, a detector 12, a getter 13, a ceramic cap 14, a VCSEL laser 15, and a thermistor 16; the support frame 2 is arranged in the LCC base 1, the U-shaped frame 5, the air chamber support 9, the second heating plate 11 and the detector 12 are sequentially arranged on the support frame 2 from bottom to top, the laser base 3, the heightening plate 4, the attenuation plate 6, the 1/4 wave plate 7 and the first heating plate 8 are sequentially arranged in the U-shaped frame 5 in the direction close to the second heating plate 11, the VCSEL laser 15 and the thermistor 16 are arranged on the laser base 3, and the detector 12 is opposite to the emitting end of the VCSEL laser 15; the atomic air chamber 10 is a square or spherical air chamber, the atomic air chamber 10 is arranged in the air chamber bracket 9, the getter 13 is arranged on the peripheries of the U-shaped frame 5 and the air chamber bracket 9, and the ceramic pipe cap 14 is arranged on the periphery of the getter 13 and is welded with the LCC base 1 in a sealing way. The suspended chip atomic clock physical system provided by the invention only needs a single optical frequency modulation method of a single laser and a single temperature control scheme, namely, all components are in the same cavity to carry out integral temperature control, instead of respectively controlling the temperature of the VCSEL laser and the atomic air chamber, so that the system has a simpler integral structure and lower production cost, can realize vacuum reflow soldering, reduces the power consumption of equipment, and provides a solid foundation for public application of the chip atomic clock.

Specifically, the LCC base 1 and the ceramic pipe cap 14 form a sealing structure through vacuum sealing welding or non-vacuum welding, and the support frame 2, the laser base 3, the VCSEL laser 15, the thermistor 16, the spacer 4, the 1/4 wave plate 7, the attenuator 6, the U-shaped frame 5, the first heating plate 8, the atomic gas chamber 10, the gas chamber bracket 9, the second heating plate 11, the detector 12 and the getter 13 are all located in the sealing structure.

The laser base 3, the first heating plate 8 and the second heating plate 11 are made of glass or quartz; metal electrodes are evaporated on the laser base 3, the first heating plate 8 and the second heating plate 11 and used for leading wires; the U-shaped frame 5 and the air chamber bracket 9 are made of silicon; the getter 13 is made of a multi-metal component such as titanium zirconium. The invention adopts various materials including glass, quartz, metal, silicon, high molecular material, ceramic and the like as the base materials, has a large selection range, and simultaneously, all the connections are bonded by adopting high-strength adhesive with high strength.

Referring to fig. 3, the support 2 includes a silicon frame 21 and a polyimide film 22 (PI film for short), the polyimide film 22 is hollowed out in the middle of the silicon frame 21, the U-shaped frame 5, the air chamber support 9, the second heating plate 11 and the detector 12 are sequentially disposed on the polyimide film 22 from bottom to top, and the support 2 separates the laser base 3 and the 1/4 wave plate 7, the attenuation plate 6, the first heating plate 8, the atomic air chamber 10, the detector 12 and other components on the laser base 3 from the LCC base 1, so as to reduce heat conduction and loss.

Specifically, the upper surface of the silicon frame 21 is a plane, the suspended polyimide film 22 is attached to the upper surface of the silicon frame 21, the lower surface of the silicon frame 21 is a plane, the shape of the silicon frame 21 is an octagonal shape formed by cutting four corners off, the frame width of the silicon frame 21 is narrower than 1mm, and the thickness is thinner than 0.6mm.

The thickness of the polyimide film 22 is 10 mu m, the polyimide film is in a 'well' shape, the rest parts except the middle part are hollowed out, the contact area between the polyimide film 22 of the support frame 21 and the laser base 3 is reduced, the heat conduction and loss are also reduced, the function of reducing the power consumption of equipment is achieved, and the polyimide film 22 is photosensitive polyimide.

The silicon frame 21 is made of hexagonal crystal silicon, and the PI film is made of photosensitive PI (photosensitive polyimide). The manufacturing process of the silicon frame-PI film comprises the following steps: the 600 mu m double polished silicon wafer is used as a substrate, photosensitive PI is coated on the front side in a spin mode, patterning and imidization are carried out, a silicon ring is etched on the back side through deep silicon etching, and the PI film is guaranteed to be completely suspended on the silicon ring.

Any combination of the technical features of the above embodiments may be performed (as long as there is no contradiction between the combination of the technical features), and for brevity of description, all of the possible combinations of the technical features of the above embodiments are not described; these examples, which are not explicitly written, should also be considered as being within the scope of the present description.

The foregoing has outlined and detailed description of the present application in terms of the general description and embodiments. It should be appreciated that numerous conventional modifications and further innovations may be made to these specific embodiments, based on the technical concepts of the present application; but such conventional modifications and further innovations may be made without departing from the technical spirit of the present application, and such conventional modifications and further innovations are also intended to fall within the scope of the claims of the present application.

Claims

1. The utility model provides a suspension type chip atomic clock physical system which is characterized in that, including LCC base, support frame, laser instrument base, VCSEL laser instrument, thermistor, rim plate, U-shaped frame, damping piece, 1/4 wave plate, first heating piece, air chamber support, atomic air chamber, second heating piece, detector, getter and ceramic tube cap, the support frame is installed in the LCC base, U-shaped frame, air chamber support, second heating piece and detector are set gradually from bottom to top on the support frame, the direction that is close to the second heating piece in the U-shaped frame has set gradually the laser instrument base, rim plate, damping piece, 1/4 wave plate and first heating piece, VCSEL laser instrument and thermistor are installed on the laser instrument base, the detector is just to the transmitting end of laser instrument, the atomic air chamber is installed in the air chamber support, the getter sets gradually in U-shaped frame and the support frame periphery air chamber cap, ceramic tube cap is installed in the welding of the peripheral seal of the LCC base and the getter;

the support frame comprises a silicon frame, a suspended polyimide film is attached to the upper surface of the silicon frame, the lower surface of the silicon frame is a plane, and the U-shaped frame, the air chamber support, the second heating plate and the detector are sequentially arranged on the polyimide film from bottom to top; the polyimide film is photosensitive polyimide; the polyimide film thickness was 10 μm; the polyimide film is shaped like a Chinese character 'jing', and the rest parts except the middle part are hollow;

the manufacturing process of the support frame comprises the following steps: and (3) taking a 600 mu m double polished silicon wafer as a substrate, spin-coating photosensitive PI on the front surface, patterning, imidizing, etching the back surface by deep silicon, and etching to obtain a silicon ring, so that the polyimide film is completely suspended on the silicon ring.

2. The physical system of claim 1, wherein the silicon frame is hexagonal crystalline silicon.

3. The suspended chip atomic clock physical system of claim 1, wherein the laser mount, the first heater chip, and the second heater chip are glass or quartz.

4. The suspended chip atomic clock physical system of claim 1, wherein the laser mount, the first heater chip, and the second heater chip are vapor deposited with metal electrodes.

5. The suspended chip atomic clock physical system of claim 1, wherein the U-shaped frame and the air chamber support are silicon.

6. The suspended chip atomic clock physical system of claim 1, wherein the getter is a multi-metal material.

7. The suspended chip atomic clock physical system of claim 1, wherein the atomic gas cell is a square or spherical gas cell.